Objective To evaluate the impact of endoscopic sphincterotomy （EST） and bile duct exploration with open surgery on immune function and inflammatory response. Methods Fifty-one patients with choledocholithiasis were divided into endoscopy group （ EG, n = 24） and laparotomy group （ LG, n = 27 ） according to the patients＇ will from June 2010 to February 2012. Procalcitonin（ PCT）, C-reactive protein （ CRP）, immunoglobulins （IgA,IgG,lgM） and T lymphocyte （ CD4 ,CD8 ） of peripheral blood were exam- ined preoperatively and on the 1st, 3rd and 5th day postoperatively. Results Compared with preoperative levels, postoperative levels of serum PCT and CRP were higher in both groups （P 〈 0. 01 ） , but on the 3rd day after the operation, the changes of PCT and CRP levels in the two groups were not significantly different （ P 〉 0. 05 ）. Postoperative levels of serum immunoglobulins of two groups were lower than preoperative levels （P 〈0. 01 ）, but the IgA and IgM levels in EG were significantly higher than those in the LG （P 〈0. 05）, and IgG levels in the two groups were not significantly different after surgery （ P 〉 0.05 ）. Compared with preoperative levels, postoperative levels of CD4, CD8 and CD4/CD8 ratio in EG were only slightly decreased （P 〉 0. 05 ） , and returned to the preoperative levels on the 5th day postoperatively, but postoperative levelsof these variables in LG were decreased significantly （ P 〈 0. 05 ）. Postoperative levels of CD4, CD8 and CIM/CD8 ration of the two groups were significantly different （P 〈 0. 05 ）. Conclusion Both EST and bile duct exploration with open surgery can inhibit immune function and induce inflammation, but the procedure of EST, which may mainly affect humoral immune function, has impact on immune function less intensely.